| 摘要 |
<p>An insert (14), such as a piston ring groove reinforcement insert, is incorporated into the piston by squeeze casting the piston crown-down with the insert (14) being located towards the base of the lower die member (10). This avoids the problems of insert warping and cracking which can arise as a result of differential solidification and contraction during solidification in crown-up squeeze casting. Crown-down squeeze casting also ensures that the skirt (17) of the piston has fully developed squeeze cast properties by avoiding premature solidification of the skirt before squeezing, which can occur in crown-up squeeze casting.</p> |
